package com.yonyougov.devops.cruxcisupport.util;

import com.yonyougov.devops.cruxcisupport.user.vo.JwtUser;
import io.jsonwebtoken.Claims;
import io.jsonwebtoken.JwtBuilder;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;

import javax.crypto.spec.SecretKeySpec;
import javax.xml.bind.DatatypeConverter;
import java.math.BigInteger;
import java.security.Key;
import java.util.Date;

public class JWTTokenUtil {
    public static JwtUser parseJWT(String jsonWebToken, String base64Security) {
        try {
            Claims claims = Jwts.parser()
                    .setSigningKey(DatatypeConverter.parseBase64Binary(base64Security))
                    .parseClaimsJws(jsonWebToken).getBody();
            JwtUser jwtUser = new JwtUser();
            jwtUser.setId(new BigInteger(claims.get("id").toString()));
            jwtUser.setEmail(claims.get("email").toString());
            jwtUser.setUserName(claims.get("userName").toString());
            return jwtUser;
        } catch (Exception ex) {
            return null;
        }
    }

    public static String createJWT(JwtUser jwtUser, long TTLMillis, String base64Security) {
        SignatureAlgorithm signatureAlgorithm = SignatureAlgorithm.HS256;

        long nowMillis = System.currentTimeMillis();
        Date now = new Date(nowMillis);

        //生成签名密钥
        byte[] apiKeySecretBytes = DatatypeConverter.parseBase64Binary(base64Security);
        Key signingKey = new SecretKeySpec(apiKeySecretBytes, signatureAlgorithm.getJcaName());

        //添加构成JWT的参数
        JwtBuilder builder = Jwts.builder().setHeaderParam("typ", "JWT")
                .claim("id", jwtUser.getId().toString())
                .claim("email", jwtUser.getEmail())
                .claim("userName", jwtUser.getUserName())
                .signWith(SignatureAlgorithm.HS512, signingKey);
        //添加Token过期时间
        if (TTLMillis >= 0) {
            long expMillis = nowMillis + TTLMillis;
            Date exp = new Date(expMillis);
            builder.setExpiration(exp).setNotBefore(now);
        }
        //生成JWT
        return builder.compact();
    }

}
